Fastening device for scaffolds



June 10, 1969 J 5. VlRKKl I 3,448,958

- FASTENING DEVICE FOR SCAFFOLDS Filed March a, 1967 rrafiNEYS United States Patent 3,448,958 FASTENING DEVICE FOR SCAFFOLDS Jalmari Selim Virkki, Tuulitie 3, Vantaa, Finland Filed Mar. 8, 1967, Ser. No. 621,638 Int. Cl. F161 3/00 U.S. Cl. 248237 5 Claims ABSTRACT OF THE DISCLOSURE A fastening device for scaffolds which are to be mounted upon the roof of a building, includes a bolt extending through a sleeve to the roof and carrying a flange which is used as a support for fastening ropes.

This invention relates to a fastening device or arrangement mounted on the roof surface of buildings, to which hanging scaffolds, safety belts and similar supporting ropes can be fastened.

The securing of scaffolds, is usually done by fastening them to projections on the roof, such as smoke and air chimneys, roof ladders, eaves gutters and other more or less unreliable points on the roof. As a consequence a number of accidents have generally been due to weak fastening points for the supporting ropes or to careless fastening of the ropes, for example by means of hooks, which now and then after the ropes having slackened have lost their grip.

The intention is to have this fault remedied by the present invention for fastening scaffolds, which while having been thoroughly thought out from the viewpoint of safety first does not in any way spoil the outside appearance of buildings.

Summary of the invention claimed The principal feature of the fastening device according to this invention is therefore characterized in that the fastening device is adapted to be fastened to the roof surface by means of a hollow bolt reaching up to it through a borehole, the bolt being in turn fitted with an inner flange bolt, which on being raised up into the open serves as a support arrangement for the fastening ropes. A rope may be passed between the flange of the inner bolt and the hollow bolt. The two bolts have intermeshing screw threads. There is also a third bolt serving as a safety bolt and pressed by a spring against the flange of the inner bolt.

The following advantages are secured by using this invention:

The fastening device is permanently mounted through the surface of the roof and is always available for use whenever required. The device being rather low and hardly noticeable does not spoil the outside appearance of buildings. The device does not cause any leak in the roof. The device being low and bevel edged does not interfere with the shovelling of snow from the roofs in 3,448,958 Patented June 10, 1969 when slackening, to get detached from the fastening arrangement.

The invention is explained below by the help of enclosed drawing, the sale figure of which is a cross-section of part of the scaffold fastening device mounted on the roof in Working position.

The drawing is showing flange 1 as attached for example by welding to the threaded bolt 2, which in turn is fitted by screw threads 17 into the hollow bolt 4, which is attached to flange 3 and being also threaded both inside and outside it enables the inner bolt to be screwed into the hollow flange bolt, which makes the bevel edged flanges form the surface of a truncated cone. Flange 1 is provided with two boreholes 15 for opening the fastening device. Hollow flange bolt 3, 4 is fastened to a hole 18 running through the roof surface and boarding 13 and also to supporting plank 14 underneath the roof surface by means of base plate 5 and tightening-up screw 6 engaging the screw threads 16 of the bolt 4. Both between flange 3 and the roof surface as well as between the flanges is fitted waterproof packing 12 made of rubber or plastics. Supporting rope 11 is fastened between the opened flanges 1 and 3. The safety device, bolt 8, is fitted into tube 9 located in the borehole 19 and pressed upwards by the spring 10, the bolt being pushed against the lower surface of flange 1, thereby preventing any unexpected unfastening of the ropes. Bolt 8 can be pressed down for the' purpose of fastening and unfastening the ropes and may have near its top a groove to fit a chisel (not showing). The tap 7 (can be threaded) prevents bolt 2 from leaving its thread altogether.

The scaffold fastening device is intended to be mounted on the roof surface near the roof ridge and about 5 meters apart in the same direction as the ridge and on both sides of it, the purpose being to serve as fastening points for the scaifolds supporting ropes. Between the gables the device is also mounted in the same way. As roofs differ in shape, the fastening device should be mounted in such a way, that the scaffolds as well as the supporting ropes of those working on the roof can be used on all sides of a building.

The invention is not confiined only to the kind of performance described above, but may be varied in different ways.

I claim:

1. A device for holding a rope upon the roof of a building, said device comprising a hollow bolt fixed to the roof and having inner screw threads, another bolt having a portion located within said hollow bolt with outer screw threads meshing with the inner screw threads of the hollow bolt and an upper portion extending above said hollow bolt, a flange carried by said upper portion, a safety bolt, and a spring pressing said safety bolt against said flange, whereby the rope may be passed below said flange and between said hollow bolt and said safety bolt.

2. A device in accordance with claim 1, further comprising a tap carried by a lower end of the bolt.

3. A device in accordance with claim 1, further comprising a flange fixed to the upper end of said hollow bolt.

4. A device in accordance with claim 3, wherein both flanges have outer circular bevelled edges having the shape of a truncated cone.

3 4 5. A device in accordance with claim 3, comprising 21 2,288,845 7/1942 Schilling 248-66 waterproof packing upon upper and lower surfaces of 3,269,679 8/1966 Grappo 248*72 the second-mentioned flange.

ROY D. FRAZIER, Primary Examiner.

References Cited 5 I. W. FOSS, Assistant Examiner. UNITED STATES PATENTS 1,732,053 10/1929 Landis 248-66 1,911,334 5/1933 Williams 24866 243-361 

